According to the know state of the art, knitted products of relevant type—in concrete terms the tights—are manufactured in such a way that the two legs are knitted separately and these are consequently straight-cut in their upper part and then they are sewn together and so the body part is created. This technology of manufacture is well developed and very sophisticated machines—usually automatic or semi-automatic textile machines—were developed for the technology performance. The main disadvantage of tights manufactured in this way is the fact that at point of inter-connection of the two legs and the tight part, the three hoses are practically connected in one point, which is extremely loaded during wearing and seam damage often occurs. Another important disadvantage is also the fact that the seam in the panties section—mainly in case of ladies tights—is significantly unaesthetic.
So as to eliminate the main disadvantage of classic manufacture of tights, there was developed the technology of gore sewing in the point of connection of legs and the body. By sewing in the gore, there was practically fully eliminated the main disadvantage. But this is a technology that has not been automated to acceptable level yet, so it brings undesirable manual operations to the production cycle, delaying the manufacturing process. The question of poor aesthetics of the seam also remained unsolved.
In the course of time, there were developed the small-diameter knitting machines, adjusted to manufacture of tights from one piece, without necessity of sewing the panty section together. There exist several categories of the knitting machines and consequently even products.
As a basic category of these products it is possible to consider tights—their manufacture in knitting industry jargon is called “knitting from toe to toe”. In case of this group of products, manufacture has been started by knitting the toe of one of the legs, it continued by knitting the body part with simultaneous creation of the waist hole and it was finished by knitting the other leg. There also known the solutions when the body part was knitted by reverse run with the purpose of obtaining bigger panties section. But this category of products showed one significant disadvantage that was not successfully eliminated and that was a cause for the products to gradually leave the markets. While in case of classic tights, the knitted fabric lines of the body section are parallel to the leg section, the number of columns of the knitted fabric in the body is twice the number of columns in the leg section. The height of the panties is practically unlimited, while in case of products in the category “knitting from toe to toe” the lines of the knitted fabric in the body section are practically perpendicular to the lines of the knitted fabric of the leg. The number of columns of the knitted fabric—that is in this case decisive for the height of the panties—is even lower than the number of columns in the leg and that causes insufficient height of the body section. That is the main cause why this category of products has not found its permanent position in the market.
Tights manufactured on small-diameter knitting machines equipped with two needle-rolls represented another category of the products. One product of this category was manufactured in such a way that knitting started by knitting the upper section by applying the reverse run simultaneously on both of the needle-rolls. After knitting the body part, there were simultaneously knitted both of the legs by rotation run, while the leg knitted on the upper roll was drafted in to the hollow of the leg knitted in the bottom needle-roll. The main disadvantages of the tights were the facts that the point of connection of both of the legs with the body part was strongly prone to the knitted fabric ripping, while the proper concept of the knitting machine did not allow required fineness of the knitted fabric to be reached, it did not allow development of patterns with exuviated face thread and strengthened patterns. There is also known a variant solution, when the body part was knitted by rotation run of the needle-rolls, while on a part of the circumference of both of the needle-rolls, the hoses were knitted together and then cut up. But the quality of such a seam was poor and it did not find any possible application in the course of time.
There is also known the category of products manufactured on single-roll knitting machines, using special exuviation jacks, respectively using a device plate. In case of this category of products there was usually knitted one of the legs at first, then approximately half of the needle-roll circumference was transferred to jacks to non-operation position and then knitting of the second leg followed. After finishing the second leg knitting, there were dropped down the links from that part of the circumference, where there were placed the links of the first leg transferred to jacks. Then, the knitting of the body part followed, using full number of knitting needles as used for knitting of both of the legs. There is also known a technical solution when—while using the device plate—there was closed the space created by putting off the knitted fabric from a part of the circumference. The main disadvantages of this category of products include insufficient number of columns of the knitted fabric in the body part of the product and mainly low aesthetic value of the products.
Seamless textile product—for example tights—could be theoretically as well as practically manufactured on popular double-bedded knitting machines. But the machines were not applied in practical manufacture mainly due to low productivity of flat knitting machines compared to small-diameter knitting machines and poor quality of product performance in case of tights.
Textile of the underwear type like boxers, panties, slips and so on are practically manufactured in two ways. The first—in fact classic—way includes manufacture of a semi-product for example on large-diameter knitting machines, cutting the semi-product to relevant shape and consequent sewing of the final product. But the classic way of manufacture has some disadvantages, including high share of manual work with small level of automation as well as the fact that the seams—mainly in the buttock area—have significantly different volume and elasticity than the remaining part of the product and they are visible under the outwear, which is frequently undesirable. The efforts aimed at reaching increased elasticity of underwear caused introduction of production technology, when the semi-product is manufactured on medium-diameter knitting machine. Then, the semi-product is cut off the main knitted fabric and the edges are sewn. But even the underwear manufactured in this way shows the above-specified disadvantageous features and more, it causes quite significant technologic waste of the expensive input material.